A motor vehicle door typically includes an outer sheet metal panel and an inner sheet metal panel connected together to form a cavity therebetween. An equipment module is often mounted to the inner sheet metal panel within the cavity. In addition, an impact beam is typically welded to the inner sheet panel to resist deformation of the door during a side impact collision. The use of equipment modules and side impact beams increases the thickness of the door, and can increase assembly costs of the vehicle door.
U.S. Pat. No. 7,040,688 to White and Chernoff, incorporated by reference herein, discloses the use of an inner door panel having an integrated impact beam. The inner panel is formed to include corrugated regions that extend convexly outwards from its wet side surface (i.e., facing towards the exterior of the vehicle). The corrugated regions provide sufficient intrusion resistance to obviate the need for an additional impact beam. To accommodate equipment mounted to the wet side surface of the inner panel (such as the rails to the window regulator), interruptions in the corrugated regions are provided.
While the above-noted inner door panel disclosed by White and Chernoff improves the strength and reduces the thickness of the door assembly relative to a conventional vehicle door, it is not without its drawbacks.
First, the corrugated regions of the integrated impact beam are limited in their size and geometry as to accommodate wet-side mounted equipment, such as providing space between the outer sheet metal and the panel for the travel of the window glass. Furthermore, the corrugated regions must be spaced apart from the outer panel as to allow free travel of the window glass.
Second, the inner panel has a large hole in it to accommodate the window regulator drive assembly. This has a deleterious effect on the structural integrity of the inner door panel, causing the design to use many more corrugations to achieve a particular side impact resistance. In addition, despite the large access hole for the window regulator motor assembly, the door assembly does readily enable certain door hardware such as the window regulator subsystem to be installed on a high speed manufacturing line. Moreover, the White and Chernoff inner panel must still be sealed to prevent moisture and road dirt from entering the passenger cabin.
It is thus desirable to provide a door assembly that includes an inner door panel that provides a high level of intrusion resistance but still allows for hardware components to be easily mounted while minimizing the thickness of the door assembly.